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Motorola T5320 FRS handheld radio

The Family Radio Service (FRS) is an improved walkie-talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies around 462 and 467 MHz in the ultra high frequency (UHF) band. It does not suffer the interference effects found on citizens' band (CB) at 27 MHz, or the 49 MHz band also used by cordless telephones, toys, and baby monitors. FRS uses frequency modulation (FM) instead of amplitude modulation (AM). Since the UHF band has different radio propagation characteristics, short-range use of FRS may be more predictable than the more powerful license-free radios operating in the HF CB band.

Initially proposed by RadioShack in 1994 for use by families, FRS has also seen significant adoption by business interests, as an unlicensed, low-cost alternative to the business band. New rules issued by the FCC in May 2017 clarify and simplify the overlap between FRS and GMRS radio services.

Worldwide, a number of similar personal radio services exist; these share the characteristics of low power, operation in the UHF (or upper VHF) band using FM, and simplified or no end-user licenses. Exact frequency allocations differ, so equipment legal to operate in one country may cause unacceptable interference in another.

Contents

Technical informationEdit

FRS radios use narrow-band frequency modulation (NBFM) with a maximum deviation of 2.5 kilohertz. The channels are spaced at 12.5 kilohertz intervals.

After May 18, 2017, FRS radios are limited to 2 Watts on channel 1-7 and channels 15-22.[1] Previously, FRS radios were limited to 500 milliwatts. Channels 1 to 7 are shared with low-power interstitial channels of General Mobile Radio Service (GMRS). A license is required for those channels if the power output is over the 2 watt FRS limits.[2]

FRS radios frequently have provisions for using sub-audible tone squelch (CTCSS and DCS) codes, filtering out unwanted chatter from other users on the same frequency. Although these codes are sometimes called "privacy codes" or "private line codes" (PL codes), they offer no protection from eavesdropping and are only intended to help share busy channels. Tone codes also do nothing to prevent desired transmissions from being swamped by stronger signals having a different code.

FRS stations on channels 1 through 7 may communicate with GMRS stations on those shared channels.[2][1]

All equipment used on FRS must be type accepted according to FCC regulations. Radios are not type-accepted for use in this service if they exceed limits on power output, have a detachable antenna or for other reasons.[2][3]

FRS radios must use only permanently attached antennas,[2] such as walkie-talkies; there are also table-top FRS "base station" radios that have whip antennas. This limitation intentionally restricts the range of communications, allowing greatest use of the available channels. The use of duplex radio repeaters and interconnects to the telephone network are prohibited under FRS rules, unlike other radio services.

FRS manufacturers generally claim exaggerated range. The presence of large buildings, trees, etc., will reduce range. Under exceptional conditions, (such as hilltop to hilltop) communication is possible over 60 km (37 mi) or more, but that is rare. Under normal conditions, with line of sight blocked by a few buildings or trees, FRS has an actual range of about 0.5 to 1.5 km (0.3 to 1 mile).

FRS/GMRS hybrid radiosEdit

In May 2017, the FCC significantly revised the rules for combination FRS/GMRS radios. Combination radios will be permitted to radiate 2 watts on all channels, and all FRS channels are now considered shared with the GMRS service. Operation over 2 watts, or operation on GMRS repeater input channels, will still required GMRS licensing. The FCC will not certify combination FRS/GMRS radios that exceed the current power limits for the FRS service.[1]

 
Motorola FV150 FRS and GMRS handheld radio

Hybrid FRS/GMRS consumer radios have been introduced that have 22 channels. Before May 2017, radios had been certified for unlicensed operation on the 7 FRS frequencies, channels 8–14, under FRS rules.[4]

Prior to the 2017 revision, FCC rules required a GMRS license to operate on channels 1–7 using more than 0.5 watts.[2] Many hybrid radios have an ERP that is lower than 0.5 watts on channels 1–7, or can be set by the user to operate at low power on these channels. This allows hybrid radios to be used under the license-free FRS rules if the ERP is less than 0.5 watts and the unit is certified for FRS operation on these frequencies.[2] Beginning September 28, 2017, FRS operation is permitted at up to 2 watts on these channels.

Interference to licensed services may be investigated by the FCC.[5]

Channels 8–14, formerly exclusive to FRS, since September 28, 2017 can be used by GMRS at 0.5 watts. Channels 15–22, formerly reserved exclusively for GMRS, can be used at up to 2 watts in the FRS.

List of FRS channels compared to GMRSEdit

Channel Frequency (MHz) FRS EIRP Restriction GMRS EIRP Restriction
1 462.5625 Up to 2 watt Up to 5 watts
2 462.5875 Up to 2 watt Up to 5 watts
3 462.6125 Up to 2 watt Up to 5 watts
4 462.6375 Up to 2 watt Up to 5 watts
5 462.6625 Up to 2 watt Up to 5 watts
6 462.6875 Up to 2 watt Up to 5 watts
7 462.7125 Up to 2 watt Up to 5 watts
8 467.5625 Up to 0.5 watt Up to 0.5 watt[6]
9 467.5875 Up to 0.5 watt Up to 0.5 watt[6]
10 467.6125 Up to 0.5 watt Up to 0.5 watt[6]
11 467.6375 Up to 0.5 watt Up to 0.5 watt[6]
12 467.6625 Up to 0.5 watt Up to 0.5 watt[6]
13 467.6875 Up to 0.5 watt Up to 0.5 watt[6]
14 467.7125 Up to 0.5 watt Up to 0.5 watt[6]
15 462.5500 Up to 2 watt Up to 50 watts
16 462.5750 Up to 2 watt Up to 50 watts
17 462.6000 Up to 2 watt Up to 50 watts
18 462.6250 Up to 2 watt Up to 50 watts
19 462.6500 Up to 2 watt Up to 50 watts
20 462.6750 Up to 2 watt Up to 50 watts
21 462.7000 Up to 2 watt Up to 50 watts
22 462.7250 Up to 2 watt Up to 50 watts
  • EIRP = Effective Isotropic Radiated Power
  • GMRS has other exclusive channels
  • FRS channels 8-14 are exclusively FRS with no detachable antenna such as found on GMRS equipment. No FRS unit shall exceed .5 watt (EIRP) Effective Isotropic Radiated Power on channels 8-14. FRS Channels 15-22 are shared with GMRS also under 2 watt EIRP limit. However, if the device includes any of the following channels (467.5500, 467.5750, 467.6000, 467.6250, 467.6500, 467.6750, 467.7000, and 467.7250 MHz) a GMRS license is required. The only benefit of a GMRS license is the ability to use a repeater and communicate longer distances. [1][6]

FRS radios in other countriesEdit

Personal UHF radio services similar to the American FRS exist in other countries, although since technical standards and frequency bands will differ, usually FCC-approved FRS equipment may not be used in other jurisdictions.

CanadaEdit

American-standard FRS radios have been approved for use in Canada since April 2000. As of 2016, only low-power (2W ERP), half duplex GMRS operation is permitted, but a license is not required.[7] Repeater and high-power operations are not permitted. This allows the use of dual-mode FRS/GMRS walkie-talkies, but precludes the use of higher-powered devices designed for vehicle and base-station purposes.

MexicoEdit

Since tourists often bring their FRS radios with them, and since trade between the U.S., Canada, and Mexico is of great value to all three countries, the Mexican Secretary of Communication and Transportation has authorized use of the FRS frequencies and equipment similar to that in the US. However, dual-mode FRS/GMRS equipment is not approved in Mexico, so caution should be exercised in operating hybrid FRS/GMRS devices purchased elsewhere.[8]

South AmericaEdit

Dual-mode GMRS/FRS equipment is also approved in Brazil (GMRS only in simplex mode, GMRS frequencies 462.550, 467.550, 462.725, 467.725 are not allowed)[9] and most other South American countries. Portable radios are heavily used in private communications, mainly by security staff in nightclubs and malls, but also in private parking, maintenance, and delivery services.

Other personal radio servicesEdit

Many personal radio services similar to the FRS exist around the world. Because radio spectrum allocation varies around the world, a personal radio service device may not be usable outside its original area of purchase. FRS equipment may not be legally permitted in other countries because it uses frequencies allocated to services such as police or fire; however, many countries have equivalents to the FRS.

See alsoEdit

ReferencesEdit

  1. ^ a b c d "FCC Part 95 Personal Radio Services Rules Reform" (PDF). Federal Communications Commission. Retrieved May 19, 2017. In paragraph 51 and 52 lists the changes on the FRS/GMRS channels and power restrictions. These modifications are meant to affect previous FRS/GMRS hybrid radios in the United State that were commonly sold to redefine them as FRS radios since many users that purchase these radios did not know the FCC license requirements. As a result, these users will not require a GMRS license. Radios transmitting higher than the new FRS power restrictions are re-defined as GMRS radios and users will require a GMRS license to use these devices. 
  2. ^ a b c d e f "General Mobile Radio Service (GMRS)". Federal Communications Commission. Retrieved November 13, 2015. If you operate a radio that has been approved for both FRS and GMRS, and if you limit your operations to the FRS channels with a maximum power of ½ watt effective radiated power and an integral antenna, you are not required to have a license. (Note that some dual-service radios transmit with higher power on FRS channels 1 through 7; these radios can be used without a license only on FRS channels 8 through 14.) 
  3. ^ http://www.fcc.gov/encyclopedia/family-radio-service-frs
  4. ^ FCC: Wireless Services: Family Radio Service: Family Home
  5. ^ "EB - Spectrum Enforcement Division". Federal Communications Commission. 26 January 2010. Retrieved 31 January 2011. The Spectrum Enforcement Division is responsible for resolution of complaints involving public safety and technical issues such as tower registration, marking and lighting and equipment requirements. The Division is also responsible for taking enforcement actions regarding such violations as unauthorized construction or operation of radio stations. 
  6. ^ a b c d e f g h GMRS transmitting on channels 8-14 must follow FRS rules that are to be hand-held units with integral antennas, transmitting power on these channels will be limited to 0.5 Watts EIRP, emission bandwidth on these channels will be limited to 12.5 kilohertz, and frequency tolerance on these channels will be held to within 2.5 parts per million (ppm).
  7. ^ "'RSS-210, Issue 9 - Low-power Licence-exempt Radiocommunication Devices (All Frequency Bands), Annex E'". Industry Canada. Retrieved 4 November 2016. 
  8. ^ https://web.archive.org/web/20091026203800/http://geocities.com/wd9ewk/xe-frs.html Mexico's Family Radio Service (FRS) equivalent retrieved 23 October 2009
  9. ^ http://www.anatel.gov.br/Portal/exibirPortalRedireciona.do?codigoDocumento=252434 RESOLUÇÃO No 506, DE 1o DE JULHO DE 2008 page 28, Seção XIV, retrieved 12 May 2012

External linksEdit